PRECISE MAPPING OF GEOTHERMAL POTENTIAL OVER SEMBALUN PROSPECT USING GEOMAGNETICS AND REMOTE SENSING

Abstract

The urgency of providing renewable energy has escalated due to the depletion of fossil fuel resources.
Lombok Island exhibits significant geothermal energy potential, particularly in the vicinity of Mount
Rinjani, known as the Sembalun prospect. Despite previous research efforts indicating this potential,
detailed mapping necessary for exploration has been lacking. This study employs geomagnetic surveys
conducted by the University of Mataram since 2004, complemented by remote sensing techniques, to
precisely identify geothermal hotspots in the Sembalun prospect. Geomagnetic ground measurements
were taken at 138 points, while Landsat 8 satellite imagery was utilized to determine land surface
temperature and vegetation indices. The results reveal three negative geomagnetic anomaly closures
coinciding with areas of sparse vegetation and high surface temperatures, covering approximately 6.5
km^2 in Sembalun Bumbung, Sembalun Lawang, and Sajang villages. These findings suggest
substantial geothermal potential suitable for direct use, particularly in supporting agricultural and
tourism sectors. Further refinement through integration with gravity data is recommended for a
comprehensive subsurface interpretation.